In the late 1960s, she worked as nanny in the English county of Kent and visited local castles and country seats.

Now, after decades of hard graft on their North Otago dairy farm, often working seven days a week, Dot and husband Neil Smith are set to move into their own dream home - Riverstone Castle.

"I'm very comfortable in England and the old houses and the old castles. So forever and a day I've wanted to build just a baby castle that we could live in," says pink-haired Dot, known as the Queen of Riverstone Castle.

"There are not many castles here in New Zealand, [if] I was in England I could've bought a little one. So we've just made one that's hopefully user-friendly for when we leave this planet and it can have a life after us."

It took three years to get building consent for the 1200sq m, two-storey castle 18kms north of Oamaru, and just visible from State Highway One, before construction finally began in 2013.

They dug the gravel out of a flat paddock, sold it to a local Oamaru shingle supply firm who turned it into concrete blocks which were then used to build the castle's main walls.

It was then surrounded by the distinctive white Oamaru stone. Internal beams were crafted from old macrocarpa trees from their property.

Related Content

She enlisted the expertise of local master builder Mike Spiers who has spent four years, with the help of apprentice Jason Anderson and sub-contractors, in realising her vision.

Now, it's nearly done. Final furnishings and carpets are going in. The place crawls with activity.

Upstairs is the most complete. It'll be available for luxury B&B accommodation, with four uniquely-styled rooms feeding off a central lounge and giant stone fireplace. Each room opens onto a huge, separate balcony.

More Property

It overlooks and, in the right light, reflects off the man-made lake, filled with irrigation water and home to baby trout, thousands of ducks and the odd heron.

Husband Neil and their grandchildren kayak in it.

A concealed door at the lakeside leads to a secret passageway through the bowels of the castle into its dungeon.

It's surrounded by a moat and will be accessed by a drawbridge - the last thing to be installed.

There will be a walled courtyard to the west, towards the Kakanui Ranges, a large fire-pit to "sit around and tell stories", a conservatory, billiards room, and lounge with massive projection unit "to watch the All Blacks".

It has all the necessary features for a true castle, with hidden panels, a main entrance hall with medieval suit of armour, swords, shields, axes, helmets, along with secret library, wrought iron chandeliers, and marble floors.

Dot took inspiration from Anne Boleyn's family home of Hever Castle which she visited in the 60s.